Euroskeptic nationalists scored stunning victories in European Parliament elections in France and Britain on Sunday as critics of the European Union more than doubled their seats in a continent-wide protest vote against austerity and unemployment.
French Prime Minister Manuel Valls called the breakthrough by Marine Le Pen's anti-immigration, anti-euro National Front in one of the EU's founding nations a political "earthquake".
Anti-establishment parties of the far right and hard left, their scores amplified by a low turnout, made gains in many countries although in Germany, the EU's biggest member state with the largest number of seats, and Italy, the pro-European center ground held firm.
In a vote that raised more doubts about Britain's long-term future in the EU, Nigel Farage's UK Independence Party, which advocates immediate withdrawal, led the opposition Labour party and Prime Minister David Cameron's Conservatives comfortably with almost half the results declared.
A jubilant Le Pen, whose party beat President Francois Hollande's ruling Socialists into third place, told supporters: "The people have spoken loud and clear ... they no longer want to be led by those outside our borders, by EU commissioners and technocrats who are unelected.
"They want to be protected from globalization and take back the reins of their destiny."
With 80 percent of votes counted, the National Front had won 26 percent of the vote, comfortably ahead of the conservative opposition UMP on 20.6 percent, with the Socialists on 13.8, their second heavy defeat in two months after losing dozens of town halls in March.
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First official results from around the 28-nation bloc showed the pro-European center-left and center-right parties will keep control of around 70 percent of the 751-seat EU legislature, but the number of Euroskeptic members will more than double.
The centre-right European People's Party, led by former Luxembourg Prime Minister Jean-Claude Juncker, was set to win 212 seats, preliminary results issued by the parliament showed.
"As the EPP has a strong lead ... I am ready to accept the mandate of the European Commission president," Juncker told reporters in parliament. "We will have a clear pro-European majority in this house."
The center-left Socialists, led by outgoing European Parliament President Martin Schulz of Germany, were in second place with 186 seats followed by the centrist liberals on 70 and the Greens on 55. Euroskeptic groups were expected to win about 141 seats, according to a Reuters estimate, the far left 43 and conservatives 44.
A glum looking Schulz would not concede defeat, telling reporters he would negotiate with other parties.
"It is a bad day for the European Union when a party with such a racist, xenophobic and anti-Semite program gets 24-25 percent of the vote in France," he said. "But these voters aren't extremists, they have lost trust, they have lost hope."
UKIP make big gains
The political fallout may be felt more strongly in national politics than at EU level, pulling mainstream conservative parties further to the right and raising pressure to crack down on immigration.
In Britain, where voting took place last Thursday, UKIP won 27.5 percent of the vote, with the Labour opposition on 25.4 percent and the Conservatives on 24 percent, although results from Scotland were still to be factored in.
That will pile pressure on Cameron, who has promised Britons an in/out referendum on EU membership in 2017 if he is re-elected next year, to take an even tougher line in Europe. His pro-European Liberal Democrat coalition partners were set to hold just one seat, a loss of nine seats.
"The whole European project has been a lie," Farage said on a television link-up with Brussels. "I don't just want Britain to leave the European Union, I want Europe to leave the European Union."
In Italy, pro-European Prime Minister Matteo Renzi's center-left Democratic Party was on course for a resounding win, building a huge lead over the anti-establishment 5-Star Movement of former comic Beppe Grillo, near complete results showed.
The anti-immigration far right People's Party topped the poll in Denmark and the extreme-right Jobbik, widely accused of racism and anti-Semitism, finished second in Hungary.
In the Netherlands, the anti-Islam, Euroskeptic Dutch Freedom Party of Geert Wilders - which plans an alliance with Le Pen - underperformed but still finished joint second in terms of seats behind a pro-European centrist opposition party.
Although 388 million Europeans were eligible to vote, fewer than half cast ballots. The turnout was officially 43.1 percent, barely higher than the 2009 nadir of 43 percent, despite efforts to personalize the election with the main political families putting forward a leading candidate, or "Spitzenkandidat".
In Germany, Chancellor Angela Merkel's Christian Democrats secured 35.3 percent of the vote, down from a 23-year-high of 41.5 percent in last year's federal election but still a clear victory. The center-left Social Democrats, her coalition partners, took 27.3 percent.
The anti-euro Alternative for Germany won seats for the first time with 7 percent, the best result so far for a conservative party created only last year to oppose bailouts and call for weaker states to be ejected from the single currency.